Project Summary/Abstract Project 1 The outcome for patients diagnosed with AML remains poor, especially for patients older than 60. The quality of remission achieved with induction therapy is a major predictor of outcomes, and ~90% of patients with detectable minimal residual disease (MRD) or incomplete platelet (CRp) or peripheral count recovery (CRi) after induction will relapse in the 1st year regardless of consolidation therapies. Although allogeneic hematopoietic cell transplant (HCT) is recommended for these patients, ~1/3 are either not candidates or choose to not have an HCT. Adoptive T cell therapy offers a novel strategy to selectively target leukemic cells with limited toxicity to the patient. We previously demonstrated AML could be therapeutically targeted with WT1-specific CD8 T cells, and, in the last grant cycle, showed that relapse of AML in high risk patients post-HCT could be prevented by infusion of donor CD8 T cells engineered to express a high affinity WT1-specific TCR. We now propose to advance this T cell therapy to non-HCT patients. This setting allows us to address many critical questions not feasible in post-HCT patients about the requirements for efficacy and the obstacles to success, including the importance of the type of CD8 T cell engineered, and the contribution of lympho-depletion to cell persistence/activity. The long-term goal is to develop a reproducibly effective T cell therapy regimen for AML that can be deployed in non-HCT as well as HCT patients. The aims are: 1. Evaluate in a Phase I/II trial the safety and potential efficacy of transduced autologous CD8+ nave (TN), central memory (TCM), or EBV-specific (TEBV) T cells expressing a high affinity TCR specific for WT1 infused after induction/consolidation in patients in morphologic CR but with MRD, Cri, or CRp after induction therapy. 2. Determine if transduced cells derived from autologous CD8+ TN, TCM, or TEBV cells have distinct abilities to persist, localize to bone marrow (BM), retain function, and/or potentially eradicate leukemic cells after in vitro expansion and in vivo transfer. Endogenous TCR gene sequences will be used to barcode the transduced cells to make it possible to distinguish the contribution of each subset in vivo in the same patient. 3. Identify biologic parameters associated with treatment success or failure, including features of the leukemia and the T cells, and gain insights into strategies to overcome treatment obstacles. Leukemia cells will be evaluated for loss of the WT1 epitope or Class I, changes in antigen processing, and expression of inhibitory molecules; T cell subsets will be evaluated and compared, including by high throughput single cell PCR, for functional pathways, exhaustion, and molecular changes that influence biologic activity.